// OSRM car engine
// Doesn't yet support hints

function OSRMEngine() {
  var previousPoints, hintData;

  return {
    id: "osrm_car",
    creditline: '<a href="http://project-osrm.org/" target="_blank">OSRM</a>',
    draggable: true,

    getRoute: function (points, callback) {
      var TURN_INSTRUCTIONS = [
        "",
        'javascripts.directions.instructions.continue_on',      // 1
        'javascripts.directions.instructions.slight_right',     // 2
        'javascripts.directions.instructions.turn_right',       // 3
        'javascripts.directions.instructions.sharp_right',      // 4
        'javascripts.directions.instructions.uturn',            // 5
        'javascripts.directions.instructions.sharp_left',       // 6
        'javascripts.directions.instructions.turn_left',        // 7
        'javascripts.directions.instructions.slight_left',      // 8
        'javascripts.directions.instructions.via_point',        // 9
        'javascripts.directions.instructions.follow',           // 10
        'javascripts.directions.instructions.roundabout',       // 11
        'javascripts.directions.instructions.leave_roundabout', // 12
        'javascripts.directions.instructions.stay_roundabout',  // 13
        'javascripts.directions.instructions.start',            // 14
        'javascripts.directions.instructions.destination',      // 15
        'javascripts.directions.instructions.against_oneway',   // 16
        'javascripts.directions.instructions.end_oneway'        // 17
      ];

      var url = document.location.protocol + "//router.project-osrm.org/viaroute?z=14&output=json&instructions=true";

      for (var i = 0; i < points.length; i++) {
        url += "&loc=" + points[i].lat + ',' + points[i].lng;
        if (hintData && previousPoints && previousPoints[i].equals(points[i])) {
          url += "&hint=" + hintData.locations[i];
        }
      }

      if (hintData && hintData.checksum) {
        url += "&checksum=" + hintData.checksum;
      }

      return $.ajax({
        url: url,
        dataType: 'json',
        success: function (data) {
          if (data.status === 207)
            return callback(true);

          previousPoints = points;
          hintData = data.hint_data;

          var line = L.PolylineUtil.decode(data.route_geometry, {
            precision: 6
          });

          var steps = [];
          for (i = 0; i < data.route_instructions.length; i++) {
            var s = data.route_instructions[i];
            var linesegend;
            var instCodes = s[0].split('-');
            var instText = "<b>" + (i + 1) + ".</b> ";
            var name = s[1] ? "<b>" + s[1] + "</b>" : I18n.t('javascripts.directions.instructions.unnamed');
            if (instCodes[0] === "11" && instCodes[1]) {
              instText += I18n.t('javascripts.directions.instructions.roundabout_with_exit', { exit: instCodes[1], name: name } );
            } else {
              instText += I18n.t(TURN_INSTRUCTIONS[instCodes[0]], { name: name });
            }
            if ((i + 1) < data.route_instructions.length) {
              linesegend = data.route_instructions[i + 1][3] + 1;
            } else {
              linesegend = s[3] + 1;
            }
            steps.push([line[s[3]], s[0].split('-')[0], instText, s[2], line.slice(s[3], linesegend)]);
          }

          callback(null, {
            line: line,
            steps: steps,
            distance: data.route_summary.total_distance,
            time: data.route_summary.total_time
          });
        }
      });
    }
  };
}

OSM.Directions.addEngine(new OSRMEngine(), true);